With the increased integration of semiconductor chips, it may be desirable to fabricate a resist capable of forming chips with finer patterns. Thus, it may be necessary to use deep-ultraviolet rays (248 nm) with a shorter wavelength than conventional g-line (436 nm) and i-line (365 nm) rays in order to form resists with these finer patterns.
Conventional chemically amplified resists typically comprise base resins having tert-butoxy carbonyl (t-BOC) pendant groups. In these resins, acidolysis usually occurs readily via an acid catalyst. However, the resins may be undesirable since they often have lower decomposition temperatures as compared to their glass transition temperatures. Thus, a potentially undesirable T-top profile of a pattern may develop in lithography. Accordingly, the resin may become increasingly sensitive to environmental contamination.